llvm/CodeGen/LexicalScopes.h

//===- LexicalScopes.cpp - Collecting lexical scope info -*- C++ -*--------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements LexicalScopes analysis.
//
// This pass collects lexical scope information and maps machine instructions
// to respective lexical scopes.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CODEGEN_LEXICALSCOPES_H
#define LLVM_CODEGEN_LEXICALSCOPES_H

#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/IR/Metadata.h"
#include "llvm/Support/DebugLoc.h"
#include "llvm/Support/ValueHandle.h"
#include <utility>
namespace llvm {

class MachineInstr;
class MachineBasicBlock;
class MachineFunction;
class LexicalScope;

//===----------------------------------------------------------------------===//
/// InsnRange - This is used to track range of instructions with identical
/// lexical scope.
///
typedef std::pair<const MachineInstr *, const MachineInstr *> InsnRange;

//===----------------------------------------------------------------------===//
/// LexicalScopes -  This class provides interface to collect and use lexical
/// scoping information from machine instruction.
///
class LexicalScopes {
public:
  LexicalScopes() : MF(NULL),  CurrentFnLexicalScope(NULL) { }
  virtual ~LexicalScopes();

  /// initialize - Scan machine function and constuct lexical scope nest.
  virtual void initialize(const MachineFunction &);

  /// releaseMemory - release memory.
  virtual void releaseMemory();
  
  /// empty - Return true if there is any lexical scope information available.
  bool empty() { return CurrentFnLexicalScope == NULL; }

  /// isCurrentFunctionScope - Return true if given lexical scope represents 
  /// current function.
  bool isCurrentFunctionScope(const LexicalScope *LS) { 
    return LS == CurrentFnLexicalScope;
  }

  /// getCurrentFunctionScope - Return lexical scope for the current function.
  LexicalScope *getCurrentFunctionScope() const { return CurrentFnLexicalScope;}

  /// getMachineBasicBlocks - Populate given set using machine basic blocks
  /// which have machine instructions that belong to lexical scope identified by
  /// DebugLoc.
  void getMachineBasicBlocks(DebugLoc DL,
                             SmallPtrSet<const MachineBasicBlock*, 4> &MBBs);

  /// dominates - Return true if DebugLoc's lexical scope dominates at least one
  /// machine instruction's lexical scope in a given machine basic block.
  bool dominates(DebugLoc DL, MachineBasicBlock *MBB);

  /// findLexicalScope - Find lexical scope, either regular or inlined, for the
  /// given DebugLoc. Return NULL if not found.
  LexicalScope *findLexicalScope(DebugLoc DL);

  /// getAbstractScopesList - Return a reference to list of abstract scopes.
  ArrayRef<LexicalScope *> getAbstractScopesList() const {
    return AbstractScopesList;
  }

  /// findAbstractScope - Find an abstract scope or return NULL.
  LexicalScope *findAbstractScope(const MDNode *N) {
    return AbstractScopeMap.lookup(N);
  }

  /// findInlinedScope - Find an inlined scope for the given DebugLoc or return
  /// NULL.
  LexicalScope *findInlinedScope(DebugLoc DL) {
    return InlinedLexicalScopeMap.lookup(DL);
  }

  /// findLexicalScope - Find regular lexical scope or return NULL.
  LexicalScope *findLexicalScope(const MDNode *N) {
    return LexicalScopeMap.lookup(N);
  }

  /// dump - Print data structures to dbgs().
  void dump();

private:

  /// getOrCreateLexicalScope - Find lexical scope for the given DebugLoc. If
  /// not available then create new lexical scope.
  LexicalScope *getOrCreateLexicalScope(DebugLoc DL);

  /// getOrCreateRegularScope - Find or create a regular lexical scope.
  LexicalScope *getOrCreateRegularScope(MDNode *Scope);

  /// getOrCreateInlinedScope - Find or create an inlined lexical scope.
  LexicalScope *getOrCreateInlinedScope(MDNode *Scope, MDNode *InlinedAt);

  /// getOrCreateAbstractScope - Find or create an abstract lexical scope.
  LexicalScope *getOrCreateAbstractScope(const MDNode *N);

  /// extractLexicalScopes - Extract instruction ranges for each lexical scopes
  /// for the given machine function.
  void extractLexicalScopes(SmallVectorImpl<InsnRange> &MIRanges,
                            DenseMap<const MachineInstr *, LexicalScope *> &M);
  void constructScopeNest(LexicalScope *Scope);
  void assignInstructionRanges(SmallVectorImpl<InsnRange> &MIRanges,
                             DenseMap<const MachineInstr *, LexicalScope *> &M);

private:
  const MachineFunction *MF;

  /// LexicalScopeMap - Tracks the scopes in the current function.  Owns the
  /// contained LexicalScope*s.
  DenseMap<const MDNode *, LexicalScope *> LexicalScopeMap;

  /// InlinedLexicalScopeMap - Tracks inlined function scopes in current function.
  DenseMap<DebugLoc, LexicalScope *> InlinedLexicalScopeMap;

  /// AbstractScopeMap - These scopes are  not included LexicalScopeMap.  
  /// AbstractScopes owns its LexicalScope*s.
  DenseMap<const MDNode *, LexicalScope *> AbstractScopeMap;

  /// AbstractScopesList - Tracks abstract scopes constructed while processing
  /// a function.
  SmallVector<LexicalScope *, 4> AbstractScopesList;

  /// CurrentFnLexicalScope - Top level scope for the current function.
  ///
  LexicalScope *CurrentFnLexicalScope;
};

//===----------------------------------------------------------------------===//
/// LexicalScope - This class is used to track scope information.
///
class LexicalScope {
  virtual void anchor();

public:
  LexicalScope(LexicalScope *P, const MDNode *D, const MDNode *I, bool A)
    : Parent(P), Desc(D), InlinedAtLocation(I), AbstractScope(A),
      LastInsn(0), FirstInsn(0), DFSIn(0), DFSOut(0) {
    if (Parent)
      Parent->addChild(this);
  }

  virtual ~LexicalScope() {}

  // Accessors.
  LexicalScope *getParent() const                { return Parent; }
  const MDNode *getDesc() const                  { return Desc; }
  const MDNode *getInlinedAt() const             { return InlinedAtLocation; }
  const MDNode *getScopeNode() const             { return Desc; }
  bool isAbstractScope() const                   { return AbstractScope; }
  SmallVectorImpl<LexicalScope *> &getChildren() { return Children; }
  SmallVectorImpl<InsnRange> &getRanges()        { return Ranges; }

  /// addChild - Add a child scope.
  void addChild(LexicalScope *S) { Children.push_back(S); }

  /// openInsnRange - This scope covers instruction range starting from MI.
  void openInsnRange(const MachineInstr *MI) {
    if (!FirstInsn)
      FirstInsn = MI;

    if (Parent)
      Parent->openInsnRange(MI);
  }

  /// extendInsnRange - Extend the current instruction range covered by
  /// this scope.
  void extendInsnRange(const MachineInstr *MI) {
    assert (FirstInsn && "MI Range is not open!");
    LastInsn = MI;
    if (Parent)
      Parent->extendInsnRange(MI);
  }

  /// closeInsnRange - Create a range based on FirstInsn and LastInsn collected
  /// until now. This is used when a new scope is encountered while walking
  /// machine instructions.
  void closeInsnRange(LexicalScope *NewScope = NULL) {
    assert (LastInsn && "Last insn missing!");
    Ranges.push_back(InsnRange(FirstInsn, LastInsn));
    FirstInsn = NULL;
    LastInsn = NULL;
    // If Parent dominates NewScope then do not close Parent's instruction
    // range.
    if (Parent && (!NewScope || !Parent->dominates(NewScope)))
      Parent->closeInsnRange(NewScope);
  }

  /// dominates - Return true if current scope dominates given lexical scope.
  bool dominates(const LexicalScope *S) const {
    if (S == this)
      return true;
    if (DFSIn < S->getDFSIn() && DFSOut > S->getDFSOut())
      return true;
    return false;
  }

  // Depth First Search support to walk and manipulate LexicalScope hierarchy.
  unsigned getDFSOut() const            { return DFSOut; }
  void setDFSOut(unsigned O)            { DFSOut = O; }
  unsigned getDFSIn() const             { return DFSIn; }
  void setDFSIn(unsigned I)             { DFSIn = I; }

  /// dump - print lexical scope.
  void dump(unsigned Indent = 0) const;

private:
  LexicalScope *Parent;                          // Parent to this scope.
  AssertingVH<const MDNode> Desc;                // Debug info descriptor.
  AssertingVH<const MDNode> InlinedAtLocation;   // Location at which this 
                                                 // scope is inlined.
  bool AbstractScope;                            // Abstract Scope
  SmallVector<LexicalScope *, 4> Children;       // Scopes defined in scope.  
                                                 // Contents not owned.
  SmallVector<InsnRange, 4> Ranges;

  const MachineInstr *LastInsn;       // Last instruction of this scope.
  const MachineInstr *FirstInsn;      // First instruction of this scope.
  unsigned DFSIn, DFSOut;             // In & Out Depth use to determine
                                      // scope nesting.
};

} // end llvm namespace

#endif
Revision:	9677
Committed:	Sun Nov 26 20:05:56 2017 UTC (6 years, 5 months ago) by laffer1
Content type:	text/plain
File size:	9296 byte(s)
Log Message:	tag 3.4
#	Content
1	//===- LexicalScopes.cpp - Collecting lexical scope info -- C++ ---------===//
2	//
3	// The LLVM Compiler Infrastructure
4	//
5	// This file is distributed under the University of Illinois Open Source
6	// License. See LICENSE.TXT for details.
7	//
8	//===----------------------------------------------------------------------===//
9	//
10	// This file implements LexicalScopes analysis.
11	//
12	// This pass collects lexical scope information and maps machine instructions
13	// to respective lexical scopes.
14	//
15	//===----------------------------------------------------------------------===//
16
17	#ifndef LLVM_CODEGEN_LEXICALSCOPES_H
18	#define LLVM_CODEGEN_LEXICALSCOPES_H
19
20	#include "llvm/ADT/ArrayRef.h"
21	#include "llvm/ADT/DenseMap.h"
22	#include "llvm/ADT/SmallPtrSet.h"
23	#include "llvm/ADT/SmallVector.h"
24	#include "llvm/IR/Metadata.h"
25	#include "llvm/Support/DebugLoc.h"
26	#include "llvm/Support/ValueHandle.h"
27	#include <utility>
28	namespace llvm {
29
30	class MachineInstr;
31	class MachineBasicBlock;
32	class MachineFunction;
33	class LexicalScope;
34
35	//===----------------------------------------------------------------------===//
36	/// InsnRange - This is used to track range of instructions with identical
37	/// lexical scope.
38	///
39	typedef std::pair<const MachineInstr , const MachineInstr > InsnRange;
40
41	//===----------------------------------------------------------------------===//
42	/// LexicalScopes - This class provides interface to collect and use lexical
43	/// scoping information from machine instruction.
44	///
45	class LexicalScopes {
46	public:
47	LexicalScopes() : MF(NULL), CurrentFnLexicalScope(NULL) { }
48	virtual ~LexicalScopes();
49
50	/// initialize - Scan machine function and constuct lexical scope nest.
51	virtual void initialize(const MachineFunction &);
52
53	/// releaseMemory - release memory.
54	virtual void releaseMemory();
55
56	/// empty - Return true if there is any lexical scope information available.
57	bool empty() { return CurrentFnLexicalScope == NULL; }
58
59	/// isCurrentFunctionScope - Return true if given lexical scope represents
60	/// current function.
61	bool isCurrentFunctionScope(const LexicalScope *LS) {
62	return LS == CurrentFnLexicalScope;
63	}
64
65	/// getCurrentFunctionScope - Return lexical scope for the current function.
66	LexicalScope *getCurrentFunctionScope() const { return CurrentFnLexicalScope;}
67
68	/// getMachineBasicBlocks - Populate given set using machine basic blocks
69	/// which have machine instructions that belong to lexical scope identified by
70	/// DebugLoc.
71	void getMachineBasicBlocks(DebugLoc DL,
72	SmallPtrSet<const MachineBasicBlock*, 4> &MBBs);
73
74	/// dominates - Return true if DebugLoc's lexical scope dominates at least one
75	/// machine instruction's lexical scope in a given machine basic block.
76	bool dominates(DebugLoc DL, MachineBasicBlock *MBB);
77
78	/// findLexicalScope - Find lexical scope, either regular or inlined, for the
79	/// given DebugLoc. Return NULL if not found.
80	LexicalScope *findLexicalScope(DebugLoc DL);
81
82	/// getAbstractScopesList - Return a reference to list of abstract scopes.
83	ArrayRef<LexicalScope *> getAbstractScopesList() const {
84	return AbstractScopesList;
85	}
86
87	/// findAbstractScope - Find an abstract scope or return NULL.
88	LexicalScope findAbstractScope(const MDNode N) {
89	return AbstractScopeMap.lookup(N);
90	}
91
92	/// findInlinedScope - Find an inlined scope for the given DebugLoc or return
93	/// NULL.
94	LexicalScope *findInlinedScope(DebugLoc DL) {
95	return InlinedLexicalScopeMap.lookup(DL);
96	}
97
98	/// findLexicalScope - Find regular lexical scope or return NULL.
99	LexicalScope findLexicalScope(const MDNode N) {
100	return LexicalScopeMap.lookup(N);
101	}
102
103	/// dump - Print data structures to dbgs().
104	void dump();
105
106	private:
107
108	/// getOrCreateLexicalScope - Find lexical scope for the given DebugLoc. If
109	/// not available then create new lexical scope.
110	LexicalScope *getOrCreateLexicalScope(DebugLoc DL);
111
112	/// getOrCreateRegularScope - Find or create a regular lexical scope.
113	LexicalScope getOrCreateRegularScope(MDNode Scope);
114
115	/// getOrCreateInlinedScope - Find or create an inlined lexical scope.
116	LexicalScope getOrCreateInlinedScope(MDNode Scope, MDNode *InlinedAt);
117
118	/// getOrCreateAbstractScope - Find or create an abstract lexical scope.
119	LexicalScope getOrCreateAbstractScope(const MDNode N);
120
121	/// extractLexicalScopes - Extract instruction ranges for each lexical scopes
122	/// for the given machine function.
123	void extractLexicalScopes(SmallVectorImpl<InsnRange> &MIRanges,
124	DenseMap<const MachineInstr , LexicalScope > &M);
125	void constructScopeNest(LexicalScope *Scope);
126	void assignInstructionRanges(SmallVectorImpl<InsnRange> &MIRanges,
127	DenseMap<const MachineInstr , LexicalScope > &M);
128
129	private:
130	const MachineFunction *MF;
131
132	/// LexicalScopeMap - Tracks the scopes in the current function. Owns the
133	/// contained LexicalScope*s.
134	DenseMap<const MDNode , LexicalScope > LexicalScopeMap;
135
136	/// InlinedLexicalScopeMap - Tracks inlined function scopes in current function.
137	DenseMap<DebugLoc, LexicalScope *> InlinedLexicalScopeMap;
138
139	/// AbstractScopeMap - These scopes are not included LexicalScopeMap.
140	/// AbstractScopes owns its LexicalScope*s.
141	DenseMap<const MDNode , LexicalScope > AbstractScopeMap;
142
143	/// AbstractScopesList - Tracks abstract scopes constructed while processing
144	/// a function.
145	SmallVector<LexicalScope *, 4> AbstractScopesList;
146
147	/// CurrentFnLexicalScope - Top level scope for the current function.
148	///
149	LexicalScope *CurrentFnLexicalScope;
150	};
151
152	//===----------------------------------------------------------------------===//
153	/// LexicalScope - This class is used to track scope information.
154	///
155	class LexicalScope {
156	virtual void anchor();
157
158	public:
159	LexicalScope(LexicalScope P, const MDNode D, const MDNode *I, bool A)
160	: Parent(P), Desc(D), InlinedAtLocation(I), AbstractScope(A),
161	LastInsn(0), FirstInsn(0), DFSIn(0), DFSOut(0) {
162	if (Parent)
163	Parent->addChild(this);
164	}
165
166	virtual ~LexicalScope() {}
167
168	// Accessors.
169	LexicalScope *getParent() const { return Parent; }
170	const MDNode *getDesc() const { return Desc; }
171	const MDNode *getInlinedAt() const { return InlinedAtLocation; }
172	const MDNode *getScopeNode() const { return Desc; }
173	bool isAbstractScope() const { return AbstractScope; }
174	SmallVectorImpl<LexicalScope *> &getChildren() { return Children; }
175	SmallVectorImpl<InsnRange> &getRanges() { return Ranges; }
176
177	/// addChild - Add a child scope.
178	void addChild(LexicalScope *S) { Children.push_back(S); }
179
180	/// openInsnRange - This scope covers instruction range starting from MI.
181	void openInsnRange(const MachineInstr *MI) {
182	if (!FirstInsn)
183	FirstInsn = MI;
184
185	if (Parent)
186	Parent->openInsnRange(MI);
187	}
188
189	/// extendInsnRange - Extend the current instruction range covered by
190	/// this scope.
191	void extendInsnRange(const MachineInstr *MI) {
192	assert (FirstInsn && "MI Range is not open!");
193	LastInsn = MI;
194	if (Parent)
195	Parent->extendInsnRange(MI);
196	}
197
198	/// closeInsnRange - Create a range based on FirstInsn and LastInsn collected
199	/// until now. This is used when a new scope is encountered while walking
200	/// machine instructions.
201	void closeInsnRange(LexicalScope *NewScope = NULL) {
202	assert (LastInsn && "Last insn missing!");
203	Ranges.push_back(InsnRange(FirstInsn, LastInsn));
204	FirstInsn = NULL;
205	LastInsn = NULL;
206	// If Parent dominates NewScope then do not close Parent's instruction
207	// range.
208	if (Parent && (!NewScope \|\| !Parent->dominates(NewScope)))
209	Parent->closeInsnRange(NewScope);
210	}
211
212	/// dominates - Return true if current scope dominates given lexical scope.
213	bool dominates(const LexicalScope *S) const {
214	if (S == this)
215	return true;
216	if (DFSIn < S->getDFSIn() && DFSOut > S->getDFSOut())
217	return true;
218	return false;
219	}
220
221	// Depth First Search support to walk and manipulate LexicalScope hierarchy.
222	unsigned getDFSOut() const { return DFSOut; }
223	void setDFSOut(unsigned O) { DFSOut = O; }
224	unsigned getDFSIn() const { return DFSIn; }
225	void setDFSIn(unsigned I) { DFSIn = I; }
226
227	/// dump - print lexical scope.
228	void dump(unsigned Indent = 0) const;
229
230	private:
231	LexicalScope *Parent; // Parent to this scope.
232	AssertingVH<const MDNode> Desc; // Debug info descriptor.
233	AssertingVH<const MDNode> InlinedAtLocation; // Location at which this
234	// scope is inlined.
235	bool AbstractScope; // Abstract Scope
236	SmallVector<LexicalScope *, 4> Children; // Scopes defined in scope.
237	// Contents not owned.
238	SmallVector<InsnRange, 4> Ranges;
239
240	const MachineInstr *LastInsn; // Last instruction of this scope.
241	const MachineInstr *FirstInsn; // First instruction of this scope.
242	unsigned DFSIn, DFSOut; // In & Out Depth use to determine
243	// scope nesting.
244	};
245
246	} // end llvm namespace
247
248	#endif